Lepidolite

Group: Silicates – phyllosilicates

Chemical composition: K(Li,Al3)(AlSi3)O10(OH,F)2

Colors: Pale lilac, colorless, yellow or gray.

Hardness: 2.5 to 3.5

Formation: Monoclinic crystal; Tabular to short prismatic form

Principal Sources: Ural Mountains, Russia; Sweden; Australia; Germany, Czech Republic; Canada; Brazil; Japan, US.

Special Notes: Lepidolite is a purple mica often used as a pigment for painting, in glazes and coloring glass. It is a major source of lithium; used to make glass and enamels. It is also used in electro-optical ceramics and for high-speed optical communications. It is one of the major sources of the rare alkali metals rubidium and caesium.